252 MESSRS. HANCOCK AND HOWSE 



rather delicate, jointed, and bifurcated once or twice at the ex- 

 tremities. The rays are longest and are much inclined on the 

 lobes, and become shorter and less inclined in the axis of the 

 fork. 



Perhaps the most curious feature in this interesting fish is 

 found in the character and mode of arrangement of the more or 

 less bony plates and rods, regarded by G-ermar as composing an 

 internal "bony skeleton;" and indeed in the general disposition 

 of the component parts there is a strong resemblance to such. 

 On examining them in detail, however, there are one or two 

 anomalous features which render it difficult to work out the ho- 

 mologies of the bones ; and the discrepancies are of a nature to 

 raise the questions, Do, indeed, all these bones really belong to 

 an endo-skeleton ? and may they not in part belong to an exo- 

 skeleton ? Before, however, entering on these points it will be 

 better to describe the form and arrangement of these peculiar 

 plates and rods. And for the sake of avoiding circumlocution, 

 and to simplify the description, we shall give to the various 

 parts distinct names, referring only occasionally to those in ge- 

 neral use, for the purpose of pointing out resemblances. 



The plates and rods are arranged in transverse series, of 

 which there are twenty-seven or twenty-eight, extending from 

 the occiput to the root of the tail, reminding one much of the 

 disposition of the transverse flakes of muscle observed on the 

 sides of the body of a fish when the skin has been removed. 

 These transverse series of plates and rods are, for the most 

 part, placed a little asunder, but are at some points in contact, 

 and occasionally seem as if imbricated. They are in contact 

 along the longitudinal middle line, which corresponds to the 

 usual lateral line or the line of the vertebral column. Here 

 there is a chain of lozenge-shaped plates or areas (/i), with their 

 angles placed lengthwise and transversely. In the centre of 

 each there is an elongated rounded edge (fig. 2, 7i') placed lon- 

 gitudinally ; these ridges resemble the mucus-tubes of the lateral 

 line of certain fishes. 



These lozenge-shaped areas or plates measure about one-tenth 

 of an inch across. From either side of each of them there 



